-# frexpl.m4 serial 4
-dnl Copyright (C) 2007 Free Software Foundation, Inc.
+# frexpl.m4 serial 9
+dnl Copyright (C) 2007-2010 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.
gl_func_frexpl=no
fi
if test $gl_func_frexpl = yes; then
- AC_DEFINE([HAVE_FREXPL], 1,
+ AC_DEFINE([HAVE_FREXPL], [1],
[Define if the frexpl() function is available.])
dnl Also check whether it's declared.
dnl MacOS X 10.3 has frexpl() in libc but doesn't declare it in <math.h>.
esac
else
gl_func_frexpl_no_libm=no
+ dnl Set REPLACE_FREXPL here because the system may have frexpl in libm.
+ REPLACE_FREXPL=1
fi
if test $gl_func_frexpl_no_libm = yes; then
- AC_DEFINE([HAVE_FREXPL_IN_LIBC], 1,
+ AC_DEFINE([HAVE_FREXPL_IN_LIBC], [1],
[Define if the frexpl() function is available in libc.])
dnl Also check whether it's declared.
dnl MacOS X 10.3 has frexpl() in libc but doesn't declare it in <math.h>.
fi
])
-dnl Test whether frexpl() works on finite numbers (this fails on AIX 5.1) and
-dnl also on infinite numbers (this fails e.g. on IRIX 6.5).
+dnl Test whether frexpl() works on finite numbers (this fails on
+dnl MacOS X 10.4/PowerPC, on AIX 5.1, and on BeOS), on denormalized numbers
+dnl (this fails on MacOS X 10.5/i386), and also on infinite numbers (this
+dnl fails e.g. on IRIX 6.5 and mingw).
AC_DEFUN([gl_FUNC_FREXPL_WORKS],
[
AC_REQUIRE([AC_PROG_CC])
AC_CACHE_CHECK([whether frexpl works], [gl_cv_func_frexpl_works],
[
AC_TRY_RUN([
+#include <float.h>
#include <math.h>
+/* Override the values of <float.h>, like done in float.in.h. */
+#if defined __i386__ && (defined __BEOS__ || defined __OpenBSD__)
+# undef LDBL_MIN_EXP
+# define LDBL_MIN_EXP (-16381)
+#endif
extern long double frexpl (long double, int *);
int main()
{
volatile long double x;
- /* Test on finite numbers. */
+ /* Test on finite numbers that fails on AIX 5.1. */
x = 16.0L;
{
int exp = -9999;
if (exp != 5)
return 1;
}
+ /* Test on finite numbers that fails on MacOS X 10.4, because its frexpl
+ function returns an invalid (incorrectly normalized) value: it returns
+ y = { 0x3fe028f5, 0xc28f5c28, 0x3c9eb851, 0xeb851eb8 }
+ but the correct result is
+ 0.505L = { 0x3fe028f5, 0xc28f5c29, 0xbc547ae1, 0x47ae1480 } */
+ x = 1.01L;
+ {
+ int exp = -9999;
+ long double y = frexpl (x, &exp);
+ if (!(exp == 1 && y == 0.505L))
+ return 1;
+ }
+ /* Test on large finite numbers. This fails on BeOS at i = 16322, while
+ LDBL_MAX_EXP = 16384.
+ In the loop end test, we test x against Infinity, rather than comparing
+ i with LDBL_MAX_EXP, because BeOS <float.h> has a wrong LDBL_MAX_EXP. */
+ {
+ int i;
+ for (i = 1, x = 1.0L; x != x + x; i++, x *= 2.0L)
+ {
+ int exp = -9999;
+ frexpl (x, &exp);
+ if (exp != i)
+ return 1;
+ }
+ }
+ /* Test on denormalized numbers. */
+ {
+ int i;
+ for (i = 1, x = 1.0L; i >= LDBL_MIN_EXP; i--, x *= 0.5L)
+ ;
+ if (x > 0.0L)
+ {
+ int exp;
+ long double y = frexpl (x, &exp);
+ /* On machines with IEEE854 arithmetic: x = 1.68105e-4932,
+ exp = -16382, y = 0.5. On MacOS X 10.5: exp = -16384, y = 0.5. */
+ if (exp != LDBL_MIN_EXP - 1)
+ return 1;
+ }
+ }
/* Test on infinite numbers. */
x = 1.0L / 0.0L;
{
return 0;
}], [gl_cv_func_frexpl_works=yes], [gl_cv_func_frexpl_works=no],
[case "$host_os" in
- aix* | irix*) gl_cv_func_frexpl_works="guessing no";;
- *) gl_cv_func_frexpl_works="guessing yes";;
+ aix* | beos* | darwin* | irix* | mingw* | pw*)
+ gl_cv_func_frexpl_works="guessing no";;
+ *) gl_cv_func_frexpl_works="guessing yes";;
esac
])
])